Reworked FPU/MMX regs, added Context and Signal handling (and test13 works)

1 files changed, 1156 insertions, 0 deletions

diff --git a/src/libtools/signals.c b/src/libtools/signals.c
new file mode 100755
index 00000000..1ff13887
--- /dev/null
+++ b/src/libtools/signals.c
@@ -0,0 +1,1156 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <signal.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <syscall.h>
+#include <stddef.h>
+#include <stdarg.h>
+#include <ucontext.h>
+#include <setjmp.h>
+#include <sys/mman.h>
+
+#include "box64context.h"
+#include "debug.h"
+#include "x64emu.h"
+#include "emu/x64emu_private.h"
+#include "emu/x64run_private.h"
+#include "signals.h"
+#include "box64stack.h"
+#include "dynarec.h"
+#include "callback.h"
+#include "x64run.h"
+#include "elfloader.h"
+#include "threads.h"
+#include "emu/x87emu_private.h"
+#include "custommem.h"
+#ifdef DYNAREC
+#include "dynablock.h"
+#include "../dynarec/dynablock_private.h"
+#endif
+
+
+typedef uint64_t x64_gregset_t[23];
+enum
+{
+  X64_R8 = 0,
+# define X64_R8         X64_R8
+  X64_R9,
+# define X64_R9         X64_R9
+  X64_R10,
+# define X64_R10        X64_R10
+  X64_R11,
+# define X64_R11        X64_R11
+  X64_R12,
+# define X64_R12        X64_R12
+  X64_R13,
+# define X64_R13        X64_R13
+  X64_R14,
+# define X64_R14        X64_R14
+  X64_R15,
+# define X64_R15        X64_R15
+  X64_RDI,
+# define X64_RDI        X64_RDI
+  X64_RSI,
+# define X64_RSI        X64_RSI
+  X64_RBP,
+# define X64_RBP        X64_RBP
+  X64_RBX,
+# define X64_RBX        X64_RBX
+  X64_RDX,
+# define X64_RDX        X64_RDX
+  X64_RAX,
+# define X64_RAX        X64_RAX
+  X64_RCX,
+# define X64_RCX        X64_RCX
+  X64_RSP,
+# define X64_RSP        X64_RSP
+  X64_RIP,
+# define X64_RIP        X64_RIP
+  X64_EFL,
+# define X64_EFL        X64_EFL
+  X64_CSGSFS,           /* Actually short cs, gs, fs, __pad0.  */
+# define X64_CSGSFS     X64_CSGSFS
+  X64_ERR,
+# define X64_ERR        X64_ERR
+  X64_TRAPNO,
+# define X64_TRAPNO     X64_TRAPNO
+  X64_OLDMASK,
+# define X64_OLDMASK    X64_OLDMASK
+  X64_CR2
+# define X64_CR2        X64_CR2
+};
+
+struct x64_fpreg
+{
+  uint64_t value;
+}__attribute__((packed));
+
+struct x64_fpxreg
+{
+  unsigned short significand[4];
+  unsigned short exponent;
+  unsigned short padding[3];
+}__attribute__((packed));
+
+struct x64_xmmreg
+{
+  uint32_t          element[4];
+}__attribute__((packed));
+
+struct x64_fpstate
+{
+  /* Regular FPU environment.  */
+  uint16_t          cw;
+  uint16_t          sw;
+  uint16_t          tw;
+  uint16_t          fop;
+  uint64_t          rip;
+  uint64_t          rdp;
+  uint32_t          mxcsr;
+  uint32_t          mxcsr_mask;
+  struct x64_fpreg  _st[8];
+  struct x64_xmmreg _xmm[16];
+  uint32_t          res[12];
+  uint32_t          res2[12];
+}__attribute__((packed));
+
+typedef struct x64_fpstate *x64_fpregset_t;
+
+typedef struct
+{
+    void *ss_sp;
+    int ss_flags;
+    size_t ss_size;
+} x64_stack_t;
+
+struct sigcontext_x64
+{
+    uint64_t    r8;
+    uint64_t    r9;
+    uint64_t    r10;
+    uint64_t    r11;
+    uint64_t    r12;
+    uint64_t    r13;
+    uint64_t    r14;
+    uint64_t    r15;
+    uint64_t    di;
+    uint64_t    si;
+    uint64_t    bp;
+    uint64_t    bx;
+    uint64_t    dx;
+    uint64_t    ax;
+    uint64_t    cx;
+    uint64_t    sp;
+    uint64_t    ip;
+    uint64_t    flags;
+    uint64_t    cs;
+    uint64_t    gs;
+    uint64_t    fs;
+    uint64_t    ss;
+    uint64_t    err;
+    uint64_t    trapno;
+    uint64_t    oldmask;
+    uint64_t    cr2;
+    uint64_t    fpstate; /* Zero when no FPU/extended context */
+    uint64_t    reserved1[8];
+};
+
+struct x64_sigcontext
+{
+    uint64_t    r8;
+    uint64_t    r9;
+    uint64_t    r10;
+    uint64_t    r11;
+    uint64_t    r12;
+    uint64_t    r13;
+    uint64_t    r14;
+    uint64_t    r15;
+    uint64_t    rdi;
+    uint64_t    rsi;
+    uint64_t    rbp;
+    uint64_t    rbx;
+    uint64_t    rdx;
+    uint64_t    rax;
+    uint64_t    rcx;
+    uint64_t    rsp;
+    uint64_t    rip;
+    uint64_t    eflags;         /* RFLAGS */
+    uint16_t    cs;
+    uint16_t    gs;
+    uint16_t    fs;
+    union {
+        uint16_t    ss;     /* If UC_SIGCONTEXT_SS */
+        uint16_t    __pad0; /* Alias name for old (!UC_SIGCONTEXT_SS) user-space */
+    };
+    uint64_t    err;
+    uint64_t    trapno;
+    uint64_t    oldmask;
+    uint64_t    cr2;
+    struct x64_fpstate  *fpstate;       /* Zero when no FPU context */
+    uint64_t    reserved1[8];
+};
+
+struct x64_libc_fpstate
+{
+  /* 64-bit FXSAVE format.  */
+  uint16_t              cwd;
+  uint16_t              swd;
+  uint16_t              ftw;
+  uint16_t              fop;
+  uint64_t              rip;
+  uint64_t              rdp;
+  uint32_t              mxcsr;
+  uint32_t              mxcr_mask;
+  struct x64_fpxreg     st[8];
+  struct x64_xmmreg     xmm[16];
+  uint32_t              res1[24];
+};
+
+typedef struct x64_mcontext_s
+{
+    x64_gregset_t gregs;
+    struct x64_libc_fpstate *fpregs;
+    uint64_t    res[8];
+} x64_mcontext_t;
+
+// /!\ signal sig_set is different than glibc __sig_set
+#define _NSIG_WORDS (128 / sizeof(unsigned long int))
+
+typedef struct {
+    unsigned long int sig[_NSIG_WORDS];
+} x64_sigset_t;
+
+typedef struct x64_ucontext_s
+{
+    uint64_t                uc_flags;
+    struct x64_ucontext_s*  uc_link;
+    x64_stack_t             uc_stack;
+    x64_mcontext_t          uc_mcontext;
+    x64_sigset_t            uc_sigmask;
+    struct x64_libc_fpstate xstate;
+    uint64_t                ssp[4];
+} x64_ucontext_t;
+
+typedef struct x64_sigframe_s {
+    uintptr_t       pretcode;   // pointer to retcode
+    int             sig;
+    x64_mcontext_t cpustate;
+    struct x64_libc_fpstate xstate;
+    uintptr_t       extramask[64-1];
+    char            retcode[8];
+} x64_sigframe_t;
+
+struct kernel_sigaction {
+        void (*k_sa_handler) (int);
+        unsigned long sa_flags;
+        void (*sa_restorer) (void);
+        unsigned long sa_mask;
+        unsigned long sa_mask2;
+};
+
+static void sigstack_destroy(void* p)
+{
+	x64_stack_t *ss = (x64_stack_t*)p;
+    free(ss);
+}
+
+static void free_signal_emu(void* p)
+{
+    if(p)
+        FreeX64Emu((x64emu_t**)&p);
+}
+
+static pthread_key_t sigstack_key;
+static pthread_once_t sigstack_key_once = PTHREAD_ONCE_INIT;
+
+static void sigstack_key_alloc() {
+	pthread_key_create(&sigstack_key, sigstack_destroy);
+}
+
+static pthread_key_t sigemu_key;
+static pthread_once_t sigemu_key_once = PTHREAD_ONCE_INIT;
+
+static void sigemu_key_alloc() {
+	pthread_key_create(&sigemu_key, free_signal_emu);
+}
+
+static x64emu_t* get_signal_emu()
+{
+    x64emu_t *emu = (x64emu_t*)pthread_getspecific(sigemu_key);
+    if(!emu) {
+        const int stsize = 8*1024;  // small stack for signal handler
+        void* stack = calloc(1, stsize);
+        emu = NewX64Emu(my_context, 0, (uintptr_t)stack, stsize, 1);
+        emu->type = EMUTYPE_SIGNAL;
+        pthread_setspecific(sigemu_key, emu);
+    }
+    return emu;
+}
+
+
+uint64_t RunFunctionHandler(int* exit, uintptr_t fnc, int nargs, ...)
+{
+    if(fnc==0 || fnc==1) {
+        printf_log(LOG_NONE, "BOX86: Warning, calling Signal function handler %s\n", fnc?"SIG_DFL":"SIG_IGN");
+        return 0;
+    }
+    uintptr_t old_start = trace_start, old_end = trace_end;
+//    trace_start = 0; trace_end = 1; // disabling trace, globably for now...
+
+    x64emu_t *emu = get_signal_emu();
+    printf_log(LOG_DEBUG, "%04d|signal function handler %p called, ESP=%p\n", GetTID(), (void*)fnc, (void*)R_RSP);
+    
+    /*SetFS(emu, default_fs);*/
+    for (int i=0; i<6; ++i)
+        emu->segs_serial[i] = 0;
+        
+    if(nargs>6)
+        R_RSP -= (nargs-6)*4;   // need to push in reverse order
+
+    uint64_t *p = (uint64_t*)R_RSP;
+
+    va_list va;
+    va_start (va, nargs);
+    for (int i=0; i<nargs; ++i) {
+        if(i<6) {
+            int nn[] = {_DI, _SI, _DX, _CX, _R8, _R9};
+            emu->regs[nn[i]].q[0] = va_arg(va, uint64_t);
+        } else {
+            *p = va_arg(va, uint64_t);
+            p++;
+        }
+    }
+    va_end (va);
+
+    EmuCall(emu, fnc);  // avoid DynaCall for now
+    if(nargs>6)
+        R_RSP+=((nargs-6)*4);
+
+    if(exit)
+        *exit = emu->exit;
+
+    uint64_t ret = R_RAX;
+
+    trace_start = old_start; trace_end = old_end;
+
+    return ret;
+}
+
+EXPORT int my_sigaltstack(x64emu_t* emu, const x64_stack_t* ss, x64_stack_t* oss)
+{
+    if(!ss && !oss) {   // this is not true, ss can be NULL to retreive oss info only
+        errno = EFAULT;
+        return -1;
+    }
+    x64emu_t *sigemu = get_signal_emu();
+	x64_stack_t *new_ss = (x64_stack_t*)pthread_getspecific(sigstack_key);
+    if(!ss) {
+        if(!new_ss) {
+            oss->ss_flags = SS_DISABLE;
+            oss->ss_sp = sigemu->init_stack;
+            oss->ss_size = sigemu->size_stack;
+        } else {
+            oss->ss_flags = new_ss->ss_flags;
+            oss->ss_sp = new_ss->ss_sp;
+            oss->ss_size = new_ss->ss_size;
+        }
+        return 0;
+    }
+    printf_log(LOG_DEBUG, "%04d|sigaltstack called ss=%p[flags=0x%x, sp=%p, ss=0x%lx], oss=%p\n", GetTID(), ss, ss->ss_flags, ss->ss_sp, ss->ss_size, oss);
+    if(ss->ss_flags && ss->ss_flags!=SS_DISABLE && ss->ss_flags!=SS_ONSTACK) {
+        errno = EINVAL;
+        return -1;
+    }
+
+    if(ss->ss_flags==SS_DISABLE) {
+        if(new_ss)
+            free(new_ss);
+        pthread_setspecific(sigstack_key, NULL);
+
+        sigemu->regs[_SP].dword[0] = ((uintptr_t)sigemu->init_stack + sigemu->size_stack) & ~7;
+        
+        return 0;
+    }
+    if(oss) {
+        if(!new_ss) {
+            oss->ss_flags = SS_DISABLE;
+            oss->ss_sp = sigemu->init_stack;
+            oss->ss_size = sigemu->size_stack;
+        } else {
+            oss->ss_flags = new_ss->ss_flags;
+            oss->ss_sp = new_ss->ss_sp;
+            oss->ss_size = new_ss->ss_size;
+        }
+    }
+    if(!new_ss)
+        new_ss = (x64_stack_t*)calloc(1, sizeof(x64_stack_t));
+    new_ss->ss_sp = ss->ss_sp;
+    new_ss->ss_size = ss->ss_size;
+
+	pthread_setspecific(sigstack_key, new_ss);
+
+    sigemu->regs[_SP].dword[0] = ((uintptr_t)new_ss->ss_sp + new_ss->ss_size - 16) & ~0x0f;
+
+    return 0;
+}
+
+
+void my_sighandler(int32_t sig)
+{
+    pthread_mutex_unlock(&my_context->mutex_trace);   // just in case
+    printf_log(LOG_DEBUG, "Sighanlder for signal #%d called (jump to %p)\n", sig, (void*)my_context->signals[sig]);
+    uintptr_t restorer = my_context->restorer[sig];
+    int exits = 0;
+    int ret = RunFunctionHandler(&exits, my_context->signals[sig], 1, sig);
+    if(exits)
+        exit(ret);
+    if(restorer)
+        RunFunctionHandler(&exits, restorer, 0);
+}
+
+#ifdef DYNAREC
+uintptr_t getX64Address(dynablock_t* db, uintptr_t arm_addr)
+{
+    uintptr_t x64addr = (uintptr_t)db->x64_addr;
+    uintptr_t armaddr = (uintptr_t)db->block;
+    int i = 0;
+    do {
+        int x64sz = 0;
+        int armsz = 0;
+        do {
+            x64sz+=db->instsize[i].x64;
+            armsz+=db->instsize[i].nat*4;
+        }
+        while(!db->instsize[++i].x64);
+        if(arm_addr>=armaddr && arm_addr<(armaddr+armsz))
+            return x64addr;
+        armaddr+=armsz;
+        x64addr+=x64sz;
+        if(arm_addr==armaddr)
+            return x64addr;
+    } while(db->instsize[i].x64 || db->instsize[i].nat);
+    return x64addr;
+}
+#endif
+
+void my_sigactionhandler_oldcode(int32_t sig, siginfo_t* info, void * ucntx, int* old_code, void* cur_db)
+{
+    // need to create some x64_ucontext????
+    pthread_mutex_unlock(&my_context->mutex_trace);   // just in case
+    printf_log(LOG_DEBUG, "Sigactionhanlder for signal #%d called (jump to %p/%s)\n", sig, (void*)my_context->signals[sig], GetNativeName((void*)my_context->signals[sig]));
+
+    uintptr_t restorer = my_context->restorer[sig];
+    // get that actual ESP first!
+    x64emu_t *emu = thread_get_emu();
+    uint64_t *frame = (uint64_t*)R_RSP;
+#if defined(DYNAREC) && defined(__arm__)
+    ucontext_t *p = (ucontext_t *)ucntx;
+    void * pc = (void*)p->uc_mcontext.arm_pc;
+    dynablock_t* db = (dynablock_t*)cur_db;//FindDynablockFromNativeAddress(pc);
+    if(db) {
+        frame = (uint32_t*)p->uc_mcontext.arm_r8;
+    }
+#endif
+    // stack tracking
+    x64emu_t *sigemu = get_signal_emu();
+	x64_stack_t *new_ss = my_context->onstack[sig]?(x64_stack_t*)pthread_getspecific(sigstack_key):NULL;
+    int used_stack = 0;
+    if(new_ss) {
+        if(new_ss->ss_flags == SS_ONSTACK) { // already using it!
+            frame = (uint64_t*)sigemu->regs[_SP].q[0];
+        } else {
+            frame = (uint64_t*)(((uintptr_t)new_ss->ss_sp + new_ss->ss_size - 16) & ~0x0f);
+            used_stack = 1;
+            new_ss->ss_flags = SS_ONSTACK;
+        }
+    }
+
+    // TODO: do I need to really setup 2 stack frame? That doesn't seems right!
+    // setup stack frame
+    // try to fill some sigcontext....
+    frame -= sizeof(x64_ucontext_t);
+    x64_ucontext_t   *sigcontext = (x64_ucontext_t*)frame;
+    // get general register
+    sigcontext->uc_mcontext.gregs[X64_R8] = R_R8;
+    sigcontext->uc_mcontext.gregs[X64_R9] = R_R9;
+    sigcontext->uc_mcontext.gregs[X64_R10] = R_R10;
+    sigcontext->uc_mcontext.gregs[X64_R11] = R_R11;
+    sigcontext->uc_mcontext.gregs[X64_R12] = R_R12;
+    sigcontext->uc_mcontext.gregs[X64_R13] = R_R13;
+    sigcontext->uc_mcontext.gregs[X64_R14] = R_R14;
+    sigcontext->uc_mcontext.gregs[X64_R15] = R_R15;
+    sigcontext->uc_mcontext.gregs[X64_RAX] = R_RAX;
+    sigcontext->uc_mcontext.gregs[X64_RCX] = R_RCX;
+    sigcontext->uc_mcontext.gregs[X64_RDX] = R_RDX;
+    sigcontext->uc_mcontext.gregs[X64_RDI] = R_RDI;
+    sigcontext->uc_mcontext.gregs[X64_RSI] = R_RSI;
+    sigcontext->uc_mcontext.gregs[X64_RBP] = R_RBP;
+    sigcontext->uc_mcontext.gregs[X64_RIP] = R_RIP;
+    sigcontext->uc_mcontext.gregs[X64_RSP] = R_RSP;
+    sigcontext->uc_mcontext.gregs[X64_RBX] = R_RBX;
+    // flags
+    sigcontext->uc_mcontext.gregs[X64_EFL] = emu->eflags.x32;
+    // get segments
+    sigcontext->uc_mcontext.gregs[X64_CSGSFS] = ((uint64_t)(R_CS)) | (((uint64_t)(R_GS))<<16) | (((uint64_t)(R_FS))<<32);
+#if defined(DYNAREC) && defined(__arm__)
+    if(db) {
+        sigcontext->uc_mcontext.gregs[X64_RAX] = p->uc_mcontext.arm_r4;
+        sigcontext->uc_mcontext.gregs[X64_RCX] = p->uc_mcontext.arm_r5;
+        sigcontext->uc_mcontext.gregs[X64_RDX] = p->uc_mcontext.arm_r6;
+        sigcontext->uc_mcontext.gregs[X64_RBX] = p->uc_mcontext.arm_r7;
+        sigcontext->uc_mcontext.gregs[X64_RSP] = p->uc_mcontext.arm_r8;
+        sigcontext->uc_mcontext.gregs[X64_RBP] = p->uc_mcontext.arm_r9;
+        sigcontext->uc_mcontext.gregs[X64_RSI] = p->uc_mcontext.arm_r10;
+        sigcontext->uc_mcontext.gregs[X64_RDI] = p->uc_mcontext.arm_fp;
+        sigcontext->uc_mcontext.gregs[X64_RIP] = getX86Address(db, (uintptr_t)pc);
+    }
+#endif
+    // get FloatPoint status
+    sigcontext->uc_mcontext.fpregs = (struct x64_libc_fpstate*)&sigcontext->xstate;
+    fpu_fxsave64(emu, &sigcontext->xstate);
+    // add custom SIGN in reserved area
+    //((unsigned int *)(&sigcontext.xstate.fpstate.padding))[8*4+12] = 0x46505853;  // not yet, when XSAVE / XRSTR will be ready
+    // get signal mask
+
+    if(!new_ss) {
+        sigcontext->uc_stack.ss_sp = sigemu->init_stack;
+        sigcontext->uc_stack.ss_size = sigemu->size_stack;
+        sigcontext->uc_stack.ss_flags = SS_DISABLE;
+    } else {
+        sigcontext->uc_stack.ss_sp = new_ss->ss_sp;
+        sigcontext->uc_stack.ss_size = new_ss->ss_size;
+        sigcontext->uc_stack.ss_flags = new_ss->ss_flags;
+    }
+    // Try to guess some X64_TRAPNO
+    /*
+    TRAP_x86_DIVIDE     = 0,   // Division by zero exception
+    TRAP_x86_TRCTRAP    = 1,   // Single-step exception
+    TRAP_x86_NMI        = 2,   // NMI interrupt
+    TRAP_x86_BPTFLT     = 3,   // Breakpoint exception
+    TRAP_x86_OFLOW      = 4,   // Overflow exception
+    TRAP_x86_BOUND      = 5,   // Bound range exception
+    TRAP_x86_PRIVINFLT  = 6,   // Invalid opcode exception
+    TRAP_x86_DNA        = 7,   // Device not available exception
+    TRAP_x86_DOUBLEFLT  = 8,   // Double fault exception
+    TRAP_x86_FPOPFLT    = 9,   // Coprocessor segment overrun
+    TRAP_x86_TSSFLT     = 10,  // Invalid TSS exception
+    TRAP_x86_SEGNPFLT   = 11,  // Segment not present exception
+    TRAP_x86_STKFLT     = 12,  // Stack fault
+    TRAP_x86_PROTFLT    = 13,  // General protection fault
+    TRAP_x86_PAGEFLT    = 14,  // Page fault
+    TRAP_x86_ARITHTRAP  = 16,  // Floating point exception
+    TRAP_x86_ALIGNFLT   = 17,  // Alignment check exception
+    TRAP_x86_MCHK       = 18,  // Machine check exception
+    TRAP_x86_CACHEFLT   = 19   // SIMD exception (via SIGFPE) if CPU is SSE capable otherwise Cache flush exception (via SIGSEV)
+    */
+    uint32_t prot = getProtection((uintptr_t)info->si_addr);
+    if(sig==SIGBUS)
+        sigcontext->uc_mcontext.gregs[X64_TRAPNO] = 17;
+    else if(sig==SIGSEGV) {
+        if((uintptr_t)info->si_addr == sigcontext->uc_mcontext.gregs[X64_RIP]) {
+            sigcontext->uc_mcontext.gregs[X64_ERR] = 0x0010;    // execution flag issue (probably)
+            sigcontext->uc_mcontext.gregs[X64_TRAPNO] = (info->si_code == SEGV_ACCERR)?13:14;
+        } else if(info->si_code==SEGV_ACCERR && !(prot&PROT_WRITE)) {
+            sigcontext->uc_mcontext.gregs[X64_ERR] = 0x0002;    // write flag issue
+            if(abs((intptr_t)info->si_addr-(intptr_t)sigcontext->uc_mcontext.gregs[X64_RSP])<16)
+                sigcontext->uc_mcontext.gregs[X64_TRAPNO] = 12; // stack overflow probably
+            else
+                sigcontext->uc_mcontext.gregs[X64_TRAPNO] = 14; // PAGE_FAULT
+        } else {
+            sigcontext->uc_mcontext.gregs[X64_TRAPNO] = (info->si_code == SEGV_ACCERR)?13:14;
+            //X64_ERR seems to be INT:8 CODE:8. So for write access segfault it's 0x0002 For a read it's 0x0004 (and 8 for exec). For an int 2d it could be 0x2D01 for example
+            sigcontext->uc_mcontext.gregs[X64_ERR] = 0x0004;    // read error? there is no execute control in box86 anyway
+        }
+        if(info->si_code == SEGV_ACCERR && old_code)
+            *old_code = -1;
+    } else if(sig==SIGFPE)
+        sigcontext->uc_mcontext.gregs[X64_TRAPNO] = 19;
+    else if(sig==SIGILL)
+        sigcontext->uc_mcontext.gregs[X64_TRAPNO] = 6;
+    // call the signal handler
+    x64_ucontext_t sigcontext_copy = *sigcontext;
+
+    // set stack pointer
+    sigemu->regs[_SP].dword[0] = (uintptr_t)frame;
+
+    // set segments
+    memcpy(sigemu->segs, emu->segs, sizeof(sigemu->segs));
+
+    int exits = 0;
+    int ret = RunFunctionHandler(&exits, my_context->signals[sig], 3, sig, info, sigcontext);
+
+    if(memcmp(sigcontext, &sigcontext_copy, sizeof(x64_ucontext_t))) {
+        emu_jmpbuf_t* ejb = GetJmpBuf();
+        if(ejb->jmpbuf_ok) {
+            #define GO(R)   if(sigcontext->uc_mcontext.gregs[X64_R##R]!=sigcontext_copy.uc_mcontext.gregs[X64_R##R]) ejb->emu->regs[_##R].dword[0]=sigcontext->uc_mcontext.gregs[X64_R##R]
+            GO(AX);
+            GO(CX);
+            GO(DX);
+            GO(DI);
+            GO(SI);
+            GO(BP);
+            GO(SP);
+            GO(BX);
+            #undef GO
+            #define GO(R)   if(sigcontext->uc_mcontext.gregs[X64_##R]!=sigcontext_copy.uc_mcontext.gregs[X64_##R]) ejb->emu->regs[_##R].dword[0]=sigcontext->uc_mcontext.gregs[X64_##R]
+            GO(R8);
+            GO(R9);
+            GO(R10);
+            GO(R11);
+            GO(R12);
+            GO(R13);
+            GO(R14);
+            GO(R15);
+            #undef GO
+            if(sigcontext->uc_mcontext.gregs[X64_RIP]!=sigcontext_copy.uc_mcontext.gregs[X64_RIP]) ejb->emu->ip.dword[0]=sigcontext->uc_mcontext.gregs[X64_RIP];
+            sigcontext->uc_mcontext.gregs[X64_RIP] = R_RIP;
+            // flags
+            if(sigcontext->uc_mcontext.gregs[X64_EFL]!=sigcontext_copy.uc_mcontext.gregs[X64_EFL]) ejb->emu->eflags.x32=sigcontext->uc_mcontext.gregs[X64_EFL];
+            // get segments
+            uint16_t seg;
+            seg = (sigcontext->uc_mcontext.gregs[X64_CSGSFS] >> 0)&0xffff;
+            #define GO(S) if(ejb->emu->segs[_##S]!=seg)  {ejb->emu->segs[_##S]=seg; ejb->emu->segs_serial[_##S] = 0;}
+            GO(CS);
+            seg = (sigcontext->uc_mcontext.gregs[X64_CSGSFS] >> 16)&0xffff;
+            GO(GS);
+            seg = (sigcontext->uc_mcontext.gregs[X64_CSGSFS] >> 32)&0xffff;
+            GO(FS);
+            #undef GO
+            printf_log(LOG_DEBUG, "Context has been changed in Sigactionhanlder, doing longjmp to resume emu\n");
+            if(old_code)
+                *old_code = -1;    // re-init the value to allow another segfault at the same place
+            if(used_stack)  // release stack
+                new_ss->ss_flags = 0;
+            longjmp(ejb->jmpbuf, 1);
+        }
+        printf_log(LOG_INFO, "Warning, context has been changed in Sigactionhanlder%s\n", (sigcontext->uc_mcontext.gregs[X64_RIP]!=sigcontext_copy.uc_mcontext.gregs[X64_RIP])?" (EIP changed)":"");
+    }
+    printf_log(LOG_DEBUG, "Sigactionhanlder main function returned (exit=%d, restorer=%p)\n", exits, (void*)restorer);
+    if(exits)
+        exit(ret);
+    if(restorer)
+        RunFunctionHandler(&exits, restorer, 0);
+    if(used_stack)  // release stack
+        new_ss->ss_flags = 0;
+}
+
+void my_box86signalhandler(int32_t sig, siginfo_t* info, void * ucntx)
+{
+    // sig==SIGSEGV || sig==SIGBUS || sig==SIGILL here!
+    int log_minimum = (my_context->is_sigaction[sig] && sig==SIGSEGV)?LOG_INFO:LOG_NONE;
+    ucontext_t *p = (ucontext_t *)ucntx;
+    void* addr = (void*)info->si_addr;  // address that triggered the issue
+    void* rsp = NULL;
+#ifdef __aarch64__
+    void * pc = (void*)p->uc_mcontext.arm_pc;
+#elif defined __x86_64__
+    void * pc = (void*)p->uc_mcontext.gregs[X64_RIP];
+#elif defined __powerpc64__
+    void * pc = (void*)p->uc_mcontext.uc_regs->gregs[PT_NIP];
+#else
+    void * pc = NULL;    // unknow arch...
+    #warning Unhandled architecture
+#endif
+#ifdef DYNAREC
+    uint32_t prot = getProtection((uintptr_t)addr);
+    dynablock_t* db = NULL;
+    int db_searched = 0;
+    if ((sig==SIGSEGV) && (addr) && (info->si_code == SEGV_ACCERR) && (prot&PROT_DYNAREC)) {
+        if(box86_dynarec_smc) {
+            dynablock_t* db_pc = NULL;
+            db_pc = FindDynablockFromNativeAddress(pc);
+            if(db_pc) {
+                db = FindDynablockFromNativeAddress(addr);
+                db_searched = 1;
+            }
+            if(db_pc && db) {
+                if (db_pc == db) {
+                    dynarec_log(LOG_NONE, "Warning: Access to protected %p from %p, inside same dynablock\n", addr, pc);            
+                }
+            }
+            if(db && db->x86_addr>= addr && (db->x86_addr+db->x86_size)<addr) {
+                dynarec_log(LOG_INFO, "Warning, addr inside current dynablock!\n");
+            }
+        }
+        dynarec_log(LOG_DEBUG, "Access to protected %p from %p, unprotecting memory (prot=%x)\n", addr, pc, prot);
+        // access error, unprotect the block (and mark them dirty)
+        if(prot&PROT_DYNAREC)   // on heavy multi-thread program, the protection can already be gone...
+            unprotectDB((uintptr_t)addr, 1);    // unprotect 1 byte... But then, the whole page will be unprotected
+        // done
+        if(prot&PROT_WRITE) return; // if there is no write permission, don't return and continue to program signal handling
+    } else if ((sig==SIGSEGV) && (addr) && (info->si_code == SEGV_ACCERR) && (prot&(PROT_READ|PROT_WRITE))) {
+        db = FindDynablockFromNativeAddress(pc);
+        db_searched = 1;
+        if(db && db->x86_addr>= addr && (db->x86_addr+db->x86_size)<addr) {
+            dynarec_log(LOG_INFO, "Warning, addr inside current dynablock!\n");
+        }
+        if(addr && pc && db) {
+            // probably a glitch due to intensive multitask...
+            dynarec_log(/*LOG_DEBUG*/LOG_INFO, "SIGSEGV with Access error on %p for %p , db=%p, retrying\n", pc, addr, db);
+            return; // try again
+        }
+    }
+#else
+    void* db = NULL;
+#endif
+    static int old_code = -1;
+    static void* old_pc = 0;
+    static void* old_addr = 0;
+    const char* signame = (sig==SIGSEGV)?"SIGSEGV":((sig==SIGBUS)?"SIGBUS":"SIGILL");
+    if(old_code==info->si_code && old_pc==pc && old_addr==addr) {
+        printf_log(log_minimum, "%04d|Double %s (code=%d, pc=%p, addr=%p)!\n", GetTID(), signame, old_code, old_pc, old_addr);
+exit(-1);
+    } else {
+#ifdef DYNAREC
+        if(!db_searched)
+            db = FindDynablockFromNativeAddress(pc);
+#endif
+        old_code = info->si_code;
+        old_pc = pc;
+        old_addr = addr;
+        const char* name = GetNativeName(pc);
+        uintptr_t x64pc = (uintptr_t)-1;
+        const char* x64name = NULL;
+        const char* elfname = NULL;
+        x64emu_t* emu = thread_get_emu();
+        x64pc = R_RIP;
+        rsp = (void*)R_RSP;
+#if defined(__arm__) && defined(DYNAREC)
+        if(db && p->uc_mcontext.arm_r0>0x10000) {
+            emu = (x64emu_t*)p->uc_mcontext.arm_r0;
+        }
+        if(db) {
+            x64pc = getX64Address(db, (uintptr_t)pc);
+            rsp = (void*)p->uc_mcontext.arm_r8;
+        }
+#endif
+        x64name = getAddrFunctionName(x64pc);
+        elfheader_t* elf = FindElfAddress(my_context, x64pc);
+        if(elf)
+            elfname = ElfName(elf);
+        if(jit_gdb) {
+            pid_t pid = getpid();
+            int v = fork(); // is this ok in a signal handler???
+            if(v) {
+                // parent process, the one that have the segfault
+                volatile int waiting = 1;
+                printf("Waiting for %s (pid %d)...\n", (jit_gdb==2)?"gdbserver":"gdb", pid);
+                while(waiting) {
+                    // using gdb, use "set waiting=0" to stop waiting...
+                    usleep(1000);
+                }
+            } else {
+                char myarg[50] = {0};
+                sprintf(myarg, "%d", pid);
+                if(jit_gdb==2)
+                    execlp("gdbserver", "gdbserver", "127.0.0.1:1234", "--attach", myarg, (char*)NULL);
+                else
+                    execlp("gdb", "gdb", "-pid", myarg, (char*)NULL);
+                exit(-1);
+            }
+        }
+#ifdef DYNAREC
+        uint32_t hash = 0;
+        if(db)
+            hash = X31_hash_code(db->x86_addr, db->x86_size);
+        printf_log(log_minimum, "%04d|%s @%p (%s) (x64pc=%p/%s:\"%s\", rsp=%p), for accessing %p (code=%d/prot=%x), db=%p(%p:%p/%p:%p/%s:%s, hash:%x/%x)", 
+            GetTID(), signame, pc, name, (void*)x64pc, elfname?elfname:"???", x64name?x64name:"???", rsp, addr, info->si_code, 
+            prot, db, db?db->block:0, db?(db->block+db->size):0, 
+            db?db->x86_addr:0, db?(db->x86_addr+db->x86_size):0, 
+            getAddrFunctionName((uintptr_t)(db?db->x86_addr:0)), (db?db->need_test:0)?"need_stest":"clean", db?db->hash:0, hash);
+#else
+        printf_log(log_minimum, "%04d|%s @%p (%s) (x64pc=%p/%s:\"%s\", rsp=%p), for accessing %p (code=%d)", GetTID(), signame, pc, name, (void*)x64pc, elfname?elfname:"???", x64name?x64name:"???", rsp, addr, info->si_code);
+#endif
+        if(sig==SIGILL)
+            printf_log(log_minimum, " opcode=%02X %02X %02X %02X %02X %02X %02X %02X\n", ((uint8_t*)pc)[0], ((uint8_t*)pc)[1], ((uint8_t*)pc)[2], ((uint8_t*)pc)[3], ((uint8_t*)pc)[4], ((uint8_t*)pc)[5], ((uint8_t*)pc)[6], ((uint8_t*)pc)[7]);
+        else if(sig==SIGBUS)
+            printf_log(log_minimum, " x86opcode=%02X %02X %02X %02X %02X %02X %02X %02X\n", ((uint8_t*)x64pc)[0], ((uint8_t*)x64pc)[1], ((uint8_t*)x64pc)[2], ((uint8_t*)x64pc)[3], ((uint8_t*)x64pc)[4], ((uint8_t*)x64pc)[5], ((uint8_t*)x64pc)[6], ((uint8_t*)x64pc)[7]);
+        else
+            printf_log(log_minimum, "\n");
+    }
+    if(my_context->signals[sig] && my_context->signals[sig]!=1) {
+        if(my_context->is_sigaction[sig])
+            my_sigactionhandler_oldcode(sig, info, ucntx, &old_code, db);
+        else
+            my_sighandler(sig);
+        return;
+    }
+    // no handler (or double identical segfault)
+    // set default and that's it, instruction will restart and default segfault handler will be called...
+    if(my_context->signals[sig]!=1)
+        signal(sig, SIG_DFL);
+}
+
+void my_sigactionhandler(int32_t sig, siginfo_t* info, void * ucntx)
+{
+    #ifdef DYNAREC
+    ucontext_t *p = (ucontext_t *)ucntx;
+    void * pc = (void*)p->uc_mcontext.arm_pc;
+    dynablock_t* db = FindDynablockFromNativeAddress(pc);
+    #else
+    void* db = NULL;
+    #endif
+
+    my_sigactionhandler_oldcode(sig, info, ucntx, NULL, db);
+}
+
+void emit_signal(x64emu_t* emu, int sig, void* addr, int code)
+{
+    ucontext_t ctx = {0};
+    void* db = NULL;
+    siginfo_t info = {0};
+    info.si_signo = sig;
+    info.si_errno = 0;
+    info.si_code = code;
+    info.si_addr = addr;
+    printf_log(LOG_INFO, "Emit Signal %d at IP=%p / addr=%p, code=%d\n", sig, (void*)R_RIP, addr, code);
+    my_sigactionhandler_oldcode(sig, &info, &ctx, NULL, db);
+}
+
+EXPORT sighandler_t my_signal(x64emu_t* emu, int signum, sighandler_t handler)
+{
+    if(signum<0 || signum>=MAX_SIGNAL)
+        return SIG_ERR;
+
+    if(signum==SIGSEGV && emu->context->no_sigsegv)
+        return 0;
+
+    // create a new handler
+    my_context->signals[signum] = (uintptr_t)handler;
+    my_context->is_sigaction[signum] = 0;
+    my_context->restorer[signum] = 0;
+    if(handler!=NULL && handler!=(sighandler_t)1) {
+        handler = my_sighandler;
+    }
+
+    if(signum==SIGSEGV || signum==SIGBUS || signum==SIGILL)
+        return 0;
+
+    return signal(signum, handler);
+}
+EXPORT sighandler_t my___sysv_signal(x64emu_t* emu, int signum, sighandler_t handler) __attribute__((alias("my_signal")));
+EXPORT sighandler_t my_sysv_signal(x64emu_t* emu, int signum, sighandler_t handler) __attribute__((alias("my_signal")));    // not completly exact
+
+int EXPORT my_sigaction(x64emu_t* emu, int signum, const x64_sigaction_t *act, x64_sigaction_t *oldact)
+{
+    if(signum<0 || signum>=MAX_SIGNAL)
+        return -1;
+    
+    if(signum==SIGSEGV && emu->context->no_sigsegv)
+        return 0;
+
+    if(signum==SIGILL && emu->context->no_sigill)
+        return 0;
+    struct sigaction newact = {0};
+    struct sigaction old = {0};
+    if(act) {
+        newact.sa_mask = act->sa_mask;
+        newact.sa_flags = act->sa_flags&~0x04000000;  // No sa_restorer...
+        if(act->sa_flags&0x04) {
+            my_context->signals[signum] = (uintptr_t)act->_u._sa_sigaction;
+            my_context->is_sigaction[signum] = 1;
+            if(act->_u._sa_handler!=NULL && act->_u._sa_handler!=(sighandler_t)1) {
+                newact.sa_sigaction = my_sigactionhandler;
+            } else
+                newact.sa_sigaction = act->_u._sa_sigaction;
+        } else {
+            my_context->signals[signum] = (uintptr_t)act->_u._sa_handler;
+            my_context->is_sigaction[signum] = 0;
+            if(act->_u._sa_handler!=NULL && act->_u._sa_handler!=(sighandler_t)1) {
+                newact.sa_handler = my_sighandler;
+            } else
+                newact.sa_handler = act->_u._sa_handler;
+        }
+        my_context->restorer[signum] = (act->sa_flags&0x04000000)?(uintptr_t)act->sa_restorer:0;
+        my_context->onstack[signum] = (act->sa_flags&SA_ONSTACK)?1:0;
+    }
+    int ret = 0;
+    if(signum!=SIGSEGV && signum!=SIGBUS && signum!=SIGILL)
+        sigaction(signum, act?&newact:NULL, oldact?&old:NULL);
+    if(oldact) {
+        oldact->sa_flags = old.sa_flags;
+        oldact->sa_mask = old.sa_mask;
+        if(old.sa_flags & 0x04)
+            oldact->_u._sa_sigaction = old.sa_sigaction; //TODO should wrap...
+        else
+            oldact->_u._sa_handler = old.sa_handler;  //TODO should wrap...
+        oldact->sa_restorer = NULL; // no handling for now...
+    }
+    return ret;
+}
+int EXPORT my___sigaction(x64emu_t* emu, int signum, const x64_sigaction_t *act, x64_sigaction_t *oldact)
+__attribute__((alias("my_sigaction")));
+
+int EXPORT my_syscall_rt_sigaction(x64emu_t* emu, int signum, const x64_sigaction_restorer_t *act, x64_sigaction_restorer_t *oldact, int sigsetsize)
+{
+    printf_log(LOG_DEBUG, "Syscall/Sigaction(signum=%d, act=%p, old=%p, size=%d)\n", signum, act, oldact, sigsetsize);
+    if(signum<0 || signum>=MAX_SIGNAL)
+        return -1;
+    
+    if(signum==SIGSEGV && emu->context->no_sigsegv)
+        return 0;
+    // TODO, how to handle sigsetsize>4?!
+    if(signum==32 || signum==33) {
+        // cannot use libc sigaction, need to use syscall!
+        struct kernel_sigaction newact = {0};
+        struct kernel_sigaction old = {0};
+        if(act) {
+            printf_log(LOG_DEBUG, " New (kernel) action flags=0x%x mask=0x%x\n", act->sa_flags, *(uint32_t*)&act->sa_mask);
+            memcpy(&newact.sa_mask, &act->sa_mask, (sigsetsize>16)?16:sigsetsize);
+            newact.sa_flags = act->sa_flags&~0x04000000;  // No sa_restorer...
+            if(act->sa_flags&0x04) {
+                my_context->signals[signum] = (uintptr_t)act->_u._sa_sigaction;
+                my_context->is_sigaction[signum] = 1;
+                if(act->_u._sa_handler!=NULL && act->_u._sa_handler!=(sighandler_t)1) {
+                    newact.k_sa_handler = (void*)my_sigactionhandler;
+                } else {
+                    newact.k_sa_handler = (void*)act->_u._sa_sigaction;
+                }
+            } else {
+                my_context->signals[signum] = (uintptr_t)act->_u._sa_handler;
+                my_context->is_sigaction[signum] = 0;
+                if(act->_u._sa_handler!=NULL && act->_u._sa_handler!=(sighandler_t)1) {
+                    newact.k_sa_handler = my_sighandler;
+                } else {
+                    newact.k_sa_handler = act->_u._sa_handler;
+                }
+            }
+            my_context->restorer[signum] = (act->sa_flags&0x04000000)?(uintptr_t)act->sa_restorer:0;
+        }
+
+        if(oldact) {
+            old.sa_flags = oldact->sa_flags;
+            memcpy(&old.sa_mask, &oldact->sa_mask, (sigsetsize>16)?16:sigsetsize);
+        }
+
+        int ret = syscall(__NR_rt_sigaction, signum, act?&newact:NULL, oldact?&old:NULL, (sigsetsize>16)?16:sigsetsize);
+        if(oldact && ret==0) {
+            oldact->sa_flags = old.sa_flags;
+            memcpy(&oldact->sa_mask, &old.sa_mask, (sigsetsize>16)?16:sigsetsize);
+            if(old.sa_flags & 0x04)
+                oldact->_u._sa_sigaction = (void*)old.k_sa_handler; //TODO should wrap...
+            else
+                oldact->_u._sa_handler = old.k_sa_handler;  //TODO should wrap...
+        }
+        return ret;
+    } else {
+        // using libc sigaction
+        struct sigaction newact = {0};
+        struct sigaction old = {0};
+        if(act) {
+            printf_log(LOG_DEBUG, " New action flags=0x%x mask=0x%lx\n", act->sa_flags, *(uint64_t*)&act->sa_mask);
+            newact.sa_mask = act->sa_mask;
+            newact.sa_flags = act->sa_flags&~0x04000000;  // No sa_restorer...
+            if(act->sa_flags&0x04) {
+                if(act->_u._sa_handler!=NULL && act->_u._sa_handler!=(sighandler_t)1) {
+                    my_context->signals[signum] = (uintptr_t)act->_u._sa_sigaction;
+                    newact.sa_sigaction = my_sigactionhandler;
+                } else {
+                    newact.sa_sigaction = act->_u._sa_sigaction;
+                }
+            } else {
+                if(act->_u._sa_handler!=NULL && act->_u._sa_handler!=(sighandler_t)1) {
+                    my_context->signals[signum] = (uintptr_t)act->_u._sa_handler;
+                    my_context->is_sigaction[signum] = 0;
+                    newact.sa_handler = my_sighandler;
+                } else {
+                    newact.sa_handler = act->_u._sa_handler;
+                }
+            }
+            my_context->restorer[signum] = (act->sa_flags&0x04000000)?(uintptr_t)act->sa_restorer:0;
+        }
+
+        if(oldact) {
+            old.sa_flags = oldact->sa_flags;
+            old.sa_mask = oldact->sa_mask;
+        }
+        int ret = 0;
+
+        if(signum!=SIGSEGV && signum!=SIGBUS && signum!=SIGILL)
+            ret = sigaction(signum, act?&newact:NULL, oldact?&old:NULL);
+        if(oldact && ret==0) {
+            oldact->sa_flags = old.sa_flags;
+            oldact->sa_mask = old.sa_mask;
+            if(old.sa_flags & 0x04)
+                oldact->_u._sa_sigaction = old.sa_sigaction; //TODO should wrap...
+            else
+                oldact->_u._sa_handler = old.sa_handler;  //TODO should wrap...
+        }
+        return ret;
+    }
+}
+
+EXPORT sighandler_t my_sigset(x64emu_t* emu, int signum, sighandler_t handler)
+{
+    // emulated SIG_HOLD
+    if(handler == (sighandler_t)2) {
+        x64_sigaction_t oact;
+        sigset_t nset;
+        sigset_t oset;
+        if (sigemptyset (&nset) < 0)
+            return (sighandler_t)-1;
+        if (sigaddset (&nset, signum) < 0)
+            return (sighandler_t)-1;
+        if (sigprocmask (SIG_BLOCK, &nset, &oset) < 0)
+            return (sighandler_t)-1;
+        if (sigismember (&oset, signum))
+            return (sighandler_t)2;
+        if (my_sigaction (emu, signum, NULL, &oact) < 0)
+            return (sighandler_t)-1;
+        return oact._u._sa_handler;
+    }
+    return my_signal(emu, signum, handler);
+}
+
+EXPORT int my_getcontext(x64emu_t* emu, void* ucp)
+{
+//    printf_log(LOG_NONE, "Warning: call to partially implemented getcontext\n");
+    x64_ucontext_t *u = (x64_ucontext_t*)ucp;
+    // stack traking
+    u->uc_stack.ss_sp = NULL;
+    u->uc_stack.ss_size = 0;    // this need to filled
+    // get general register
+    u->uc_mcontext.gregs[X64_RAX] = R_RAX;
+    u->uc_mcontext.gregs[X64_RCX] = R_RCX;
+    u->uc_mcontext.gregs[X64_RDX] = R_RDX;
+    u->uc_mcontext.gregs[X64_RDI] = R_RDI;
+    u->uc_mcontext.gregs[X64_RSI] = R_RSI;
+    u->uc_mcontext.gregs[X64_RBP] = R_RBP;
+    u->uc_mcontext.gregs[X64_RIP] = *(uint64_t*)R_RSP;
+    u->uc_mcontext.gregs[X64_RSP] = R_RSP+sizeof(uintptr_t);
+    u->uc_mcontext.gregs[X64_RBX] = R_RBX;
+    u->uc_mcontext.gregs[X64_R8] = R_R8;
+    u->uc_mcontext.gregs[X64_R9] = R_R9;
+    u->uc_mcontext.gregs[X64_R10] = R_R10;
+    u->uc_mcontext.gregs[X64_R11] = R_R11;
+    u->uc_mcontext.gregs[X64_R12] = R_R12;
+    u->uc_mcontext.gregs[X64_R13] = R_R13;
+    u->uc_mcontext.gregs[X64_R14] = R_R14;
+    u->uc_mcontext.gregs[X64_R15] = R_R15;
+    // get segments
+    u->uc_mcontext.gregs[X64_CSGSFS] = ((uint64_t)(R_CS)) | (((uint64_t)(R_GS))<<16) | (((uint64_t)(R_FS))<<32);
+    // get FloatPoint status
+    // get signal mask
+    sigprocmask(SIG_SETMASK, NULL, (sigset_t*)&u->uc_sigmask);
+
+    return 0;
+}
+
+EXPORT int my_setcontext(x64emu_t* emu, void* ucp)
+{
+//    printf_log(LOG_NONE, "Warning: call to partially implemented setcontext\n");
+    x64_ucontext_t *u = (x64_ucontext_t*)ucp;
+    // stack tracking
+    emu->init_stack = u->uc_stack.ss_sp;
+    emu->size_stack = u->uc_stack.ss_size;
+    // set general register
+    R_RAX = u->uc_mcontext.gregs[X64_RAX];
+    R_RCX = u->uc_mcontext.gregs[X64_RCX];
+    R_RDX = u->uc_mcontext.gregs[X64_RDX];
+    R_RDI = u->uc_mcontext.gregs[X64_RDI];
+    R_RSI = u->uc_mcontext.gregs[X64_RSI];
+    R_RBP = u->uc_mcontext.gregs[X64_RBP];
+    R_RIP = u->uc_mcontext.gregs[X64_RIP];
+    R_RSP = u->uc_mcontext.gregs[X64_RSP];
+    R_RBX = u->uc_mcontext.gregs[X64_RBX];
+    R_R8  = u->uc_mcontext.gregs[X64_R8];
+    R_R9  = u->uc_mcontext.gregs[X64_R9];
+    R_R10 = u->uc_mcontext.gregs[X64_R10];
+    R_R11 = u->uc_mcontext.gregs[X64_R11];
+    R_R12 = u->uc_mcontext.gregs[X64_R12];
+    R_R13 = u->uc_mcontext.gregs[X64_R13];
+    R_R14 = u->uc_mcontext.gregs[X64_R14];
+    R_R15 = u->uc_mcontext.gregs[X64_R15];
+    // get segments
+    R_CS = (u->uc_mcontext.gregs[X64_CSGSFS]>> 0)&0xffff;
+    R_GS = (u->uc_mcontext.gregs[X64_CSGSFS]>>16)&0xffff;
+    R_FS = (u->uc_mcontext.gregs[X64_CSGSFS]>>32)&0xffff;
+    // set FloatPoint status
+    // set signal mask
+    //sigprocmask(SIG_SETMASK, NULL, (sigset_t*)&u->uc_sigmask);
+    // set uc_link
+    emu->uc_link = u->uc_link;
+
+    return R_EAX;
+}
+
+EXPORT int my_makecontext(x64emu_t* emu, void* ucp, void* fnc, int32_t argc, int64_t* argv)
+{
+//    printf_log(LOG_NONE, "Warning: call to unimplemented makecontext\n");
+    x64_ucontext_t *u = (x64_ucontext_t*)ucp;
+    // setup stack
+    uintptr_t* rsp = (uintptr_t*)(u->uc_stack.ss_sp + u->uc_stack.ss_size - sizeof(uintptr_t));
+    // setup the function
+    u->uc_mcontext.gregs[X64_RIP] = (intptr_t)fnc;
+    // setup args
+    int n = 3;
+    int j = 0;
+    int regs_abi[] = {_DI, _SI, _DX, _CX, _R8, _R9};
+    for (int i=0; i<argc; ++i) {
+        // get value first
+        uint64_t v;
+        if(n<6)
+            v = emu->regs[regs_abi[n++]].q[0];
+        else
+            v = argv[j++];
+        // push value
+        switch(i) {
+            case 0: u->uc_mcontext.gregs[X64_RDI] = v; break;
+            case 1: u->uc_mcontext.gregs[X64_RSI] = v; break;
+            case 2: u->uc_mcontext.gregs[X64_RDX] = v; break;
+            case 3: u->uc_mcontext.gregs[X64_RCX] = v; break;
+            case 4: u->uc_mcontext.gregs[X64_R8] = v; break;
+            case 5: u->uc_mcontext.gregs[X64_R9] = v; break;
+            default:
+                --rsp;
+                *rsp = argv[(argc-1)-i];
+        }
+    }
+    // push the return value
+    --rsp;
+    *rsp = (uintptr_t)GetExit();
+    u->uc_mcontext.gregs[X64_RSP] = (uintptr_t)rsp;
+    
+    return 0;
+}
+
+EXPORT int my_swapcontext(x64emu_t* emu, void* ucp1, void* ucp2)
+{
+//    printf_log(LOG_NONE, "Warning: call to unimplemented swapcontext\n");
+    // grab current context in ucp1
+    my_getcontext(emu, ucp1);
+    // activate ucp2
+    my_setcontext(emu, ucp2);
+    return 0;
+}
+
+void init_signal_helper(box64context_t* context)
+{
+    // setup signal handling
+    for(int i=0; i<MAX_SIGNAL; ++i) {
+        context->signals[i] = 1;    // SIG_DFL
+    }
+	struct sigaction action;
+	action.sa_flags = SA_SIGINFO | SA_RESTART | SA_NODEFER;
+	action.sa_sigaction = my_box86signalhandler;
+    sigaction(SIGSEGV, &action, NULL);
+	action.sa_flags = SA_SIGINFO | SA_RESTART | SA_NODEFER;
+	action.sa_sigaction = my_box86signalhandler;
+    sigaction(SIGBUS, &action, NULL);
+	action.sa_flags = SA_SIGINFO | SA_RESTART | SA_NODEFER;
+	action.sa_sigaction = my_box86signalhandler;
+    sigaction(SIGILL, &action, NULL);
+
+	pthread_once(&sigstack_key_once, sigstack_key_alloc);
+	pthread_once(&sigemu_key_once, sigemu_key_alloc);
+}
+
+void fini_signal_helper()
+{
+    signal(SIGSEGV, SIG_DFL);
+    signal(SIGBUS, SIG_DFL);
+    signal(SIGILL, SIG_DFL);
+}